[tyrone.s]

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Wow, that is sharp. Those Topcor lenses (and Topcon cameras) were / are fantastic! Nice shot by the way.

I think the Yashica DSB Lenses got a particularly bad Internet wrap for poor performance - kind of a repeat of a repeat of a repeat of someone's comment. Earlier M42 Yashinon's were excellent as were the lenses attached to their rangefinders. Why DSB's should be so terrible was always a bit of a mystery to me. I certainly enjoyed the irony of them being only single coated and therefore undesirable when I saw the range of 'special' limited edition single coated Cosina Voigtlander lenses released a while back. Single coated apparently being quite good for B&W.

[Douglas_of_Sweden]

Has anyone of you converted a Topcon UV lens? I have problems to even find info on the registration distance of the UV system. But while RE lenses have picked up in price the last couple of years with converters, replacement mounts etc available, the UV lenses are still dirt cheap. So I am getting tempted. But it is hard to find info on the mount mechanisms or even the reg distance.

[aliasant]

Has anyone of you converted a Topcon UV lens? I have problems to even find info on the registration distance of the UV system. But while RE lenses have picked up in price the last couple of years with converters, replacement mounts etc available, the UV lenses are still dirt cheap. So I am getting tempted. But it is hard to find info on the mount mechanisms or even the reg distance.

Tried to help but failed....
Couldnt find anything useful.

I have a nice Topcon IC1 lens that I would like to convert. The register for that one is 55mm but the lens itself doesnt have any aperture controls since those are fixed on to the camera.

Do you have a UV lens to play with already?

[bobpur]

Hi

Topcon and exacta are 44.7mm

[Damian]

Topcon and exacta are 44.7mm

Topcon UV lenses use a different mount and registration distance then the RE-Topcor / Exakta mount. There is also no aperture assembly in the lens. It's mounted on the camera.

Douglas, from what I've heard, and I could be wrong, the UV Topcor system was thier "budget" camera system and most of the lenses are not of sufficient quality to bother with. I have no first hand experience so, as I said, I could be wrong. There are decent deals out there for RE-topcor's, you just have to be patient and keep looking. Also, since you will be taking the lens partially aprat for the conversion, you may not want to discount buying lenses with "issues". You can usually get them quite cheap. I picked up my 58 1.4 for under $50 because of "issues". I also recently missed (was at work) a 35 2.8 with stuck aperture blades go for under $40 on ebay. I really need to download the ebay app for my android.

Sorry I haven't been around for a while. Work, scouts, children and family, have kept me very busy these last 3 months. I still have not completed my 58 1.4 and it doesn't look like I will have time for at least a few more months. Until then, it sits on my desk in front of me to be admired for it's aesthetic beauty.

[Douglas_of_Sweden]

Aha, so no aperture mechanism in the lens...then I understand why they go that cheap. Not sure I want that. Why on earth did they develop a new mount when the already had their exakta mount (you know of course Pentax and Topcon made similar choices...the two best established pre-existing mounts where the m42 and the exakta, and they took one each)? The only reason I had thought about was that the exakta mount was not that wide so it limited how fast lenses you could build...like the m42, but instead it is a sort of budget solution!?!
RE lenses are not that inexpensive here in Sweden. Topcon was a very small player on the Swedish market compared to for example their share of the US market, so they are rare, and have some cult status. For many other brands I can usually get lenses less expensive here than on international platforms like ebay, if I have some patience, but Topcon RE goes for about the same.

[fiveseven]

Was wondering if anyone here knows on how to obtain step-up ring or a reducer ring..... I'm looking for M43 to M52 ring for a opt block/focusing helicoid.
Lens block is M43- Helicoid is M52
Appreciate any help/advise.

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Last edited by fiveseven; 02-27-2012 at 11:48 AM.

[Damian]

Was wondering if anyone here knows on how to obtain step-up ring or a reducer ring..... I'm looking for M43 to M52 ring for a opt block/focusing helicoid.
Lens block is M43- Helicoid is M52
Appreciate any help/advise.

I really have no idea. Maybe an industrial fastener / tool company like Granger or Fastenal. Otherwise maybe you can cannibalize a part from an old broken zoom lens. Otherwise probably need to have it fabricated. Maybe someone else would have a better idea..... aliasant.......ripit...... ovim.......

[aliasant]

I really have no idea. Maybe an industrial fastener / tool company like Granger or Fastenal. Otherwise maybe you can cannibalize a part from an old broken zoom lens. Otherwise probably need to have it fabricated. Maybe someone else would have a better idea..... aliasant.......ripit...... ovim.......

Thanx for the confidence but I really have no clue.
Sounds like something that has to be made for that specific purpose in some machine shop or similar.

Oh. Wait. I have an idea.

Gaffa!

[ripit]

I really have no idea. Maybe an industrial fastener / tool company like Granger or Fastenal. Otherwise maybe you can cannibalize a part from an old broken zoom lens. Otherwise probably need to have it fabricated. Maybe someone else would have a better idea..... aliasant.......ripit...... ovim.......

I'm not sure what thread pitch you are looking for but if it corresponds to a filter thread size, you can get pretty odd sizes from ebay.

43mm to 52mm
43mm-52mm 43-52mm 43to52 Step-Up Filter Ring Adapter new black H052 | eBay
52mm to 43mm
52mm-43mm 52-43mm 52 to 43 Step Down Ring Adapter | eBay

I didn't check out these sellers, I just picked one. Just search 43mm 52mm step ring or 52mm 43mm step ring
most of these sellers ship world wide pretty cheap.

[fiveseven]

^
Thanks but filter step up rings wont work in this case.
Threads are on the wrong side. Even with the reverse rings it won't work.

I guess I just have to think of something somehow.
Wish had more experience with metal fabricating and had access to some machines. Oh well.

The lens block I was trying to mount to helicoid is Lomo RO60-1

[ripit]

^
Thanks but filter step up rings wont work in this case.
Threads are on the wrong side. Even with the reverse rings it won't work.

I guess I just have to think of something somehow.
Wish had more experience with metal fabricating and had access to some machines. Oh well.

The lens block I was trying to mount to helicoid is Lomo RO60-1

Are filter threads the right size threads though? If so, and size of the adapter isn't critical, you still should be able to adapt any thread to any thread with a combination of step/macro reversal rings.

Maybe this will give you an idea or two. Century precision optics 0.65x wide angle lens, originally sold for about 600$ but got if for 24$ shipped as it fits an obsolete bayonet mount. Took the lock ring off a cheap Chinese plastic hood (which has filter threads). Cut it into a bayonet (could have used a step down ring with a lot more work). Used a 58mm-52mm step down ring to get more space from the lens and reduce mount a little. Use a 52mm macro ring to revers the threads from female to male.

step rings album | Ripit2 | Fotki.com, photo and video sharing made easy.

With the right combination of rings, you should be able to create just about any male to male, female to female, or male to female combination. I'm not sure if that would work for what you are trying to do. I'm not familiar with the parts you are trying to mate. What is the attachment you need (for instance, do you need to go 43mm male to 52mm male?). Will filter threads work?

[kacansas03]

I have seen stranger thread adapters(adaptors ?) on various web sites. If you google thread rings, or filter rings, adapters (spelled both ways) you will find amazing things. Quite often on eBay you can find some of the different size rings but they are harder to search for since they always want to "help" you find what you are looking for, makes it easy to get lost on eBay. If is just threads I think you could find it but if it is some other kind of mount on one of the units then search for mount adapters. Good luck and keep us posted on your progress.
Alan.

Was wondering if anyone here knows on how to obtain step-up ring or a reducer ring..... I'm looking for M43 to M52 ring for a opt block/focusing helicoid.
Lens block is M43- Helicoid is M52
Appreciate any help/advise.

[Nesster]

Bellows, on a K100D. The 1c doesn't mention Zeiss so it is after WW1 started, so I'm thinking this is from the 1920s. I pull it out every now and then.

[Douglas_of_Sweden]

Have anyone converted a lens for the Agfa Sillette? I have a Agfa Color-Telinear 1:4/90 on its way. It is even hard to find info on the registration distance, but I think it is somewhere around 44-45mm, so it is likely to take surgery to get it mounted on a Pentax DSLR.